Piano sound board



Se t. 10, 1929. E. J. DISLER PIANO SOUND BOARD Filed Dec. 22, 1926 Patented Sept. 10, 1929.

UNITE STATES ENOS J. DISLER, OF TIFFIN, OHIO.

PIANO SOUND BOARD.

Application filed December 22, 1926. Serial No. 156,481.

This invention relates to sounding boards for ianos.

T e primary object of this invention is to provide, in a manner as hereinafter set forth, a piano sound board of improved construction in which the natural expansion due to moisture in the atmosphere is neutralized, to maintain the manufacturers intended bridge tension upon the string at all times and consequently maintaining a uniform volume and quality of tone heretofore found impos-' sible with the conventional type of sound board construction.

. The invention contemplates the provision of a soundboard having a series of expansion slots cut in the face of the bridge side thereof. These slots may be extended from edge to edge of the board parallel with the grain, or they may be broken and made up in the form of a plurality of staggered slots. These slots compensate for expansion and contraction of the board due to its absorption of moisture from the air and therefore, as above set forth, maintains the strings at an even tension at all times for the production of a uniform quality of tone.

Other objects and advantages of the invention will become apparent as the description of the same proceeds, and the invention will be best understood from a consideration of the following detailed description taken in connection with the accompanying drawings forming a part of this specification with the understanding, however, that the invention is not confined to any strict conformity with the showing of the drawings but may be changed or modified so long as such changes or modifications mark no material departure from the salient features of the invention as expressed in the appended claims,

In the drawings:

Figure 1 shows a sound board in top plan constructed in accordance with this invention.

Figure 2 is a section taken upon the line 2-2 of Figure 1, and,

Figure 3 is a plan view of a sound board showing the slots formed therein in short lengths instead of extending from edge to edge continuously as in Figure 1.

Referring now to the drawings in detail wherein like numerals of reference indicate corresponding parts throughout the several views, the numeral 1 indicates a sound board generally of the usual construction and having the usual rib members indicated in dotted lines and characterized by the numerals 2, extending from edge to edge upon the under side of the board transversely to the bridge members 8 and 4 which are secured to the top of the board.

Cut into the top face of the board 1 substantially parallel with the grain of the board, is a plurality of spaced parallel slots 5 which may be substantially one-sixteenth of an inch (1/16 in.) wide and cut from edge to edge of the board and arranged at intervals of approximately three inches (3 in.). The slots do not extend entirely through the board but within substantially one-sixteenth of an inch (1/16 in.) of the under side thereof.

These slots act as expansion slots when the board which is oven dried in the usual manner, absorbs moisture from the atmosphere and swells as a result. Under ordinary conditions this expansion of the board would cause increased tension of the strings whereas in a board constructed in accordance with this invention the expansion is taken up by the slots and therefore the string tension is maintained constant.

In connection with the showing of Figure 3, the same principle applies except that the slots here shown are not continuous from edge to edge of the board but are formed in 1 the bridge side of the board in short lengths as indicated by the numeral 6.

Having thus described my invention, what I claim is: 90

1. A sound board comprising a board body having expansion grooves cut therein, said grooves being of less depth than the thickness of the body and opening out through one face only of the body, a bridge secured to said face of the body, and ribs secured to the other face of the body.

2. A sound board comprising a board body having expansion grooves cut therein parallel to the grain thereof, said grooves being I of less depth than the thickness of the body and opening out through one face only of the body, a bridge secured to said face of the body, and ribs secured to the other face of 5 the body.

3. A piano sound board, comprising a board body having a plurality of spaced substantially parallel grooves formed in one face thereof and extending substantially par-' allel with the grain of the wood of the board, and a bridge secured to the grooved face of the board and extending substantially parallel with said grooves.

In testimony whereof I aifix my signature.

ENOS J. DISLER. 

